Sash balance



June 10, 1930; A;H. KERsTlNG n 1,762,821'

SASH BALANCE Filed July 51, 1928 Jaya..

ATTORNEY Patented June 19,1930

i 1,762,8zi

UNITED ST'TS 'PATENT *Q'FgFlfCf i ALBERT n. KERSTING, on Losnienrns, GALIFORNA j sAsn BALANC Application inea my 31, 1923.1 ser'ialNo. 296,575.' l

for devices of this nature; second, to furnish. superior means for applying frictional re-YV sistance to the rotating elements of such devices;third to afford facilities,'exterior to the housing, for adjusting said frictional resistance; and, fourth, to accomplish these results in a very simple and inexpensiveconstruction. Y Y

These objects are attained in the manner illustrated in the accompanying drawings, in

. whichd Figure 1 is a lateralsection'through the Casing of thedevice, on the line'l-l of Fig. 2, showing the internalparts in elevation;

Figure 2 is a cross section of the invention on the line 2-2 of Fig. 1,'the internal parts being in elevation;

Figure 3 s a portion of the housing of the device; and

Figure 4 is a perspective view of the `housi ing cover.

Similar reference numerals refer. to similar parts throughout `the several views; Y' The embodiment of my invention selected for illustration comprises; a housing formed of a side plate v5, havingV an integral 'web 6 at the front, bent at right angles thereto; a

` face plate 7, spot-weldedto the web, as at the points 8; a tubular, arbor 9, projecting inwardly from plate 5;

and. a @over 1Q, adapted to engage web 6 and- 1 plate 5,. i

perspective view of the mainV longitudinally split, Y, l

` bon steel, 'slightly spring is BPQUQ@ 'arbor 9, ltofform aclosed housing, in cooperation with the last'lnamed. parts and the side z 'The arbor 9 is. ait-*11, i

and coverlO is provided'fwith arcuate-slots 12,-through which thecastellated portions of the arbor maybe,passed'. Web 6 is deformed,- as shown at,13,'to Vform a pocket in coopera- -tion with face plate7 and `coverlO isfpro.- k,vided with aninwardly'bent tongue 14,jat v,

its yforward edge,4 15, adapted for being iinlserted inY said pocket. yThe cover is `also ,asl at; 16, at all portions ,of f

flanged `inwardly, y its periphery except itsforward edge.Y Y f,

A flanged-'cupVV pulleyl 17 lis Y rotatably mounted upon arbor 9 ;.a"ndy a spiral spring 18, within the pulley, hasits outer endconnected )orting tape 2-1 i'siwoundy upon thelouter rim of pulley17.` Sash tape Y21v extendsoutwardly through ,suitable orifices `in webs 6 andface plate 7, as at 22.

tothe pulley at19,'and its inner'end engaged i Ain slot 20of the arbon- A metallic sash-sup .Obviously the construction describedfaly lows of winding up spring 18 to the point where .its tensionV vwill `be lapproxi,mately y,the

same ,as the opposed pullof tape 21, exerted by-reason ofthe sash'load. However, in the case; of any spring sash balancing device, it is well known that thepftension ofthe supporting spring cannot exactlyequal the sashload at all points ofthe sash` travel This is` for While the sprin'gtensionfvaries between certain limits, and,V depends Iuponv f the position of` the sash.` consequence of these. con-v ditions vit desirable to introduce ,frictional means for y,preventing movement fof the sash under the influence Offgravity, `when its "weight is not perfectly balanced by theY sashpulley springe 7 Isuppl-ythenecessary friction bythe use of a floating spring,23, of ribbent. as shown. This between, Pulley l? and In `my device thereason that thesash loadvis' constant,

'any direction within its limits.

the inner wall of cover 10, and its dimensions and shape are such that it is retained in that position by web 6, arbor 9, and liange 16. Itl is,'however, free to move slightly in The center of this spring bears against the inner wall of cover l0, and near its respective ends it bears upon the face of iiange 24 of the pulley.

The parts of my sash balance are assembled as described, and the assembling is completed by upsetting or riveting the castellated portions l1, as shown at 25. vSpring 23, prior to assembling, is so bent that the pressure it exerts against pulley flange 24 will afford approximately the desired amount of friction. If more friction is desired 'for any reason, I have provided a very simple manner whereby it may be obtained. This consists of merely denting cover l inwardly as at 26, opposite the central portion of spring 23, by means of a vball-pene hammer or a round-nose punch.

It frequently happens that, when sash-balancing devices are to be removed from a window casing for any purpose, workmen insert Screwdrivers or other tools beneath face plates 7 and pry outwardly. In prior constructions this often has had the effect of bending'the face plates or loosening their connections to the housings. In my improved construction the face plate is rigidly attached, near one edge, to side plate through the integral web 6; and, near the other edge7 to cover 10 by means of tongue 14. As a consequence it is very rigid and 'cannot readily sash-tape wound upon the drum and extending outwardly through the casing; and a floating bar spring of which the ends resiliently press against the drum and the center reacts against one of said side walls, adapted to frictionally oppose the rotation of the drum; the latter said wall being adaptedcfor inward indentation by a hammer blow at the spring reaction point, whereby the pressure of theV spring may be increased without otherwise affecting the positioning or functioning of the several parts of the device.

ALBERT I-I. KERSTING.

become sprung by the use of tools to remove the device from a window casing.

. I particularly desire to call attention to my improved method for applying a yielding frictional resistance to the rotation of the pulley; and to the very simple and effective means for increasing this resistance if it should become necessary.

- Having thus fully described my I cla-im: y

' l. A device of the character described, comprising; a casing; a rotatable'drum within the casing; a sash-tape wound upon the drum `and extending outwardly through the casing; and a spring resiliently `pressing against the drum and reacting against a wall o the casing, adapted to fric-tionally oppose the rotation of the drum; the casing "being invention,

, adapted `'for permitting said wall tov be in- 1: wardly indented by a hammer blow at the springreaction point,to increase 4the pressure of the spring without otherwise affecting the positioning or' functioning of the several parts of the device.

2. Ardevice of the character described comprising; a casing` having opposedv side wallsilixedly spaced throughout the extent of their peripheries; an arbor fixedly spac Ving the central `portions of said walls; a drum rotatably mounted upon said arbor; a 

